3-hydroxy-11-keto-delta22-ergostene and esters thereof



United States Patent Ofifice 2,897,214 Patented July 28, 19593-HYDROXY-11-KETO-A -ERGOSTENE AND ESTERS THEREOF 3 Claims. (Cl.260397.2)

This application is a division of copending applications Serial No.215,026, filed March 10, 1951, now abandoned, and Serial No. 247,563,filed September 20, 1951, now Patent No. 2,854,451.

This invention is concerned with novel chemical compounds of thecyclopentanopolyhydrophenanthrene series and processes for preparing thesame; more particularly, it relates to novelcyclopentanopolyhydrophenanthrene compounds having functionalsubstituents in ring C; and specifically it relates to new compoundshaving a hydroxyl or keto substituent at the 11 position, and toprocesses for the preparation of such compounds.

Compounds of the adrenal cortex, such as Kendalls Compound E(cortisone), have been found to be of great value in the treatment ofvarious diseases. Further, it is likely that Kendalls Compound E and/orother closely related ll-hydroxysteroids will find increasingtherapeutic use in the future. Unfortunately, the only method for thepreparation of such compounds presently available utilizes desoxycholicor cholic acids as the starting material. Cholic and desoxycholic acidshave hydroxy substituents in ring C at the 12-position, thus providing ameans for introducing a functional substituent at the 11 position.However cholic and desoxycholic acids, which are obtained from animalbile, are only available in limited amounts. Heretofore no practicalmethod was available whereby a functional group could be introduced inring C which would permit the use of more abundant steroids such as thesterols, ergosterol, cholesterol, stigmasterol, or plant sapogenins,such as diosgenin, tigogenin, and the like.

It is an object of the present invention to provide a process forintroducing a functional group in ring C at the 11 position. It is afurther object to provide a process for convertingcyclopentanopolyhydrophenanthrene compounds having a double bond in the7:8 position to the corresponding cyclopentanopolyhydro phenanthrenecompound having a hydroxyl or keto group at positions 7 and 11. Anotherobject is to provide new compounds of the steroid series havingfunctional groups in ring C suitable for the preparation of othercyclopentanopolyhydrophenanthrene compounds. Other objects will beapparent from the detailed description hereinafter provided.

In accordance with our invention, we have now found that compounds ofthe cyclopentanopolyhydrophenanthrene series having an ll-ketosubstituent can be synthesized by reactions indicated as follows:

VII

There reactions are carried out as follows:

A cyclopentanopolyhydrophenanthrene compound having a 7 :8 double bond(1) is reacted with mercuric acetate producing the correspondingcompound having conjugated double bonds in the 7:8 and 9:11 positions(II) which is treated with a per acid, thus forming an epoxiderepresented by the alternate Formulas IIIA and IIIB. (At present theexact structure of the epoxide is not known and it is represented by thealternative forms IIIA and IIIB. Alternatively it is possible that theproduct obtained is a mixture of these two forms.) This epoxide is thentreated with an adsorbent to form the corresponding A -7,11-dihydroXycompound (IV).

The A -7,11-dihydroxy compound (IV) is reacted with an oxidizing agentto convert the hydroxy substituents to keto groups, thus obtaining thecorresponding A -7,1ldiketo cyclopentanopolyhydrophenanthrenederivatives (V). These diketo compounds are then reduced to saturate theA double bond and form the corresponding 7,11-diketo compound VI. Thesaturated diketo compound is then reduced to eliminate the 7-ketosubstituent, thus producing the corresponding ll-keto compound (VII).The latter compounds are useful intermediates for the preparation ofll-keto compounds having desirable therapeutic properties.

The A' -cornpounds of the cyclopentanopolyhydrophenanthrene series areconveniently prepared by reacting the corresponding A' -compound withmercuric ace tate. We have found that this reaction is preferablyeffected by reacting the A -compound with mercuric ace tate and glacialacetic acid in the presence of a suitable solvent medium such aschloroform. The reaction is conveniently conducted by stirring thereaction mixture for 16-24 hours. After the reaction is completed, the N-compound is recovered from the reaction mixture by removing theprecipitated mercurous acetate, and concentrating the solution underdiminished pressure. If desired, the residue may be further purified bycrystallization from suitable solvents. Thus, this process can beutilized to-prepare A -pregnadiene-3-ol-2O-one-3-ace tate, and A-dehydrotigogenin acetate from A' -preg nenolone acetate and A'-dehydrotigogenin acetate respectively. Alternatively, other acylderivatives of these starting materials or the 3-hydroxy compounds maybe utilized as starting materials in our process to prepare thecorresponding Ew -compounds.

Further, the 3-hydroxyA -choladienic acid, which is also useful as astarting material in the processes of The starting materials used in theprocess of this invention, namely, the 7,11-diketo compounds shown byFormula VI, may be obtained as described in copending application,,Serial No. 215,026, filed March 10, 1951.

Pursuant to our invention, we have found that the 7,11 -diketocyclopentanopolyhydrophenanthrene compounds can be reduced to thecorresponding ll-keto compounds. We prefer to effect this reduction byreacting the 7,11-diketo compound with hydrazine hydrate and an alkalimetal hydroxide at elevated temperatures in a high boilingsolventmcdium, for example, .diethylene glycol. It ,is. surprising thatunder ,these reaction conditions the l-Llsetomgroup is .notsimultaneously reduced along with the 7-keto .group. :Qnthe contrary,,we. have ,found that .under optimumconditions excellent yields of the.desired 11-keto. compo,unds .are obtained, ;by. this ,reduction process.

.Thus,.in accordance with the-processes described above3.-hydroxy-l'leketo-Az -ergostene, .-3-.hydr.0.xy,-,11 ketobis-'norallocholanic acid, 3.-hydr,oxy-11-ketotigogenin, and. thecorresponding .-.esters,,,-acyl derivatives, or jesterifiedacylderivatives can be. prepared from ,the corresponding 7,11-diketo.compounds. .=;-'If desired, ;,these 3.-h}{dr oxy-l1.-ketcompounds may. be oxidized ..-to obtain the. 3,11-diketo compounds inaccordance with methods .lgnownLin-the art.

he .11=keto cyclopentanopolyhydrophenanthrene compounds obtainedaby .theprocesses of ..our invention can be .used asstarting materials. in thepreparation of other steroid compounds .such ..as. Kendalls Compound -E.or CompoundF.

EXAMPLE '1 A mixture of 1 got 3-acetoxy-.7,11-ciilgeto A ergo stene,50c. of diethylene glycol, 0.455 g. powdered :potassium hydroxide and0.5 cc. of 85% hydrazine hydrate was heated at a temperature of.132 C.for l hour. The temperature. .Was;then. raised to 190-200 C. and thereaction mixture was heldat thistemperaturefor 2 ho urs. Water was,allowedtodistilLofi duringflhis, heating period.

.Fifteen .;cubic centimeters of water were added to the cool,ed reaction mixture and ,then the ,dark brown suspension ,was acidified withhydrochloric acid and filtered. The brown product, was dissolved in. hotacetone, filtered andv ,then treated ,with, charcoal (Darco) and filred. T so vent w s; e pora in. ;stt .=i .ei., i rog nand v 4 the residuedissolved in 25 cc. of benzene and chromatographed on 20 g. of acidwashed alumina.

The column was developed with the following solvents:

9 E9 1? Ether @Methanol .Ethyl acetate Qb rsfe Acetone 'I he benzenefractions yield a brown amorphous sol id. All other fractions were emptyor gave brown tars.

:The ,brown amorphous vfmaterialwas dissolved in 30 cc. of benzene and510 cc. ,of petroleum ,ether added and the solution chromatographed on20 g. of 'acid washed alumina. The chromatograph was developed with the.t ll wi sq re ts i r ls m e her/ e ze 1 Benzene :Methanol 2:36 grams of3,-acetoxy-lLketo-MF-ergostenewas.disso1ved,:in 7 5 cc. of chloroformand treated with .ozoneat 0C. ."Thereaction .mixturewasdi1uted.with.100,cc..of glacial. acetic acid .and oxidized at roomtemperature. .with 1 g. of chromic acid,.dissolved-.in 1.cc. .of Waterand 50 cc...of glacial acetic. acid. .isivecubiccentimeters.ofLmethanoLwere added to .destroyexcesslchromic acidand .the solvent .was removedin .vacuo..to. almost .dryness.The.residueinjhefiaskwas dissolved-by shakingtwice withamixturetof100.cc. of benzene-andfiOcc. of-5% sulfuricacid. wThe combinedaqueousacid solution was extracted with, an additional .50 .cc. of benzene.:The combined .rbenzene .extractswere washed with-50 .cc. of waterand-driedover anhydrousmagnesium sulfate. The benzenewaslemoved:inwacuoand.theresidue .dissolved 1 1112 50 cc.. of ether. i

The. ethereal solution was stirred .with5 g.-of anhydrous sodiumcarbonate and 10 cc. of water for 45 .minutes. s'Ilheietherlayertwasremovedtby decantation .andQthe aqueous layen washed.twicebydecantationwithcther.

u aTheraqueous lay-enwas-acidified with-50% sulfuric acid and theliberated-acid-3 acetoxy-ll-keto-bisnorallocholanic acid was extractedinto ether and separated from .the aqueous layer. V

The ethereal solution of the acid was treated with an ethereal solutionof diazomethaine andthe ether evaporated to small volume on the steambath whereupon the methyhester crystallized out. Yield 750 mg.Recrystallized fron1 .methanol the substance m ethyl 3-acetoxy-11-ketobisnorallocholanate, melted at 191194 C.

Analysis.-.-Calc. for C H O C, 71.73; H, 8.91. Found: C, 71.89; H, 9.15.

5 EXAMPLE 3 Preparation of methyl 3,11-diketbisnorallocholanate from3-acetoxy-11-ketobisnorallocholanate 750 mg. of methyl 3-acetoxy-ll-ketobisnorallocholanate (prepared as shown in Example 2) was refluxedwith 30 cc. of potassium hydroxide for one half hour. Fifty cubiccentimeters of water were added, the precipitated product was filteredand washed with water. The product, methyl3-hydroxy-11-ketobisnorallocholanate, melted at 176-1785 C.

The 3-hydroxy compound was dissolved in approximately 30 cc. of acetoneand oxidized at room temperature by addition of 200 mg. of chromiumtrioxide in 5 cc. of 1 N sulfuric acid. The oxidizing agent was addeddropwise with stirring over a period of one half hour. The reactionmixture was stirred an additional minutes, 1 cc. of methanol was addedand the precipitated chromium salts filtered 0E.

The acetone solution was diluted with approximately 100 cc. of waterwhich precipitated the product. After cooling, the product was filteredoh and washed with water. Recrystallized from acetone the substance,methyl 3,11-diketobisnorallocholanate, melted at 201204 C. Mixed meltingpoint with an authentic sample 201204 C. Mixed melting point with thecisisomer 171193 C. Yield 250 mg. 37% yield, [a] =+63.

Analysis.Calc. for C H O C, 73.96; H, 8.90. Found: C, 74.18; H, 9.20.

EXAMPLE 4 Methyl 3-hydroxy-11-ket0 bisn0rall0cholanate OOOH AeO-

OOOOHa GOOCHQv III IV One gram of 3-acetoxy-7,1l-diketo-A -ergostene (I)obtained as described in copending application Serial No. 215,026, filedMarch 10, 1951, was dissolved in 100 cc. of chloroform and ozone waspassed through at ice bath temperature until the approximate theoreticalamount of ozone was absorbed. The reaction mixture was diluted with 100cc. of glacial acetic acid, cooled to 5 C. and oxidized with 0.5 g.chromic acid dissolved in 0.75 cc. water and 50 cc. glacial acetic acid.

After standing overnight, 5 cc. of methanol was added and the solventwas removed in vacuo to practically dryness. The residue in the flaskwas dissolved by shaking twice with a mixture of 25 cc. of 5% sulfuricacid and 50 cc. of benzene. The combined benzene solutions were driedover anhydrous magnesium sulfate, and the benzene was evaporated on thesteam bath in a stream of nitrogen.

The residue was dissolved in 200 cc. of ether and stirred with 5 g. ofsodium carbonate and 2 cc. of water for 21 hours. The sodium salt of3-acetoxy-7,11-diketobisnorallocholanic acid (II) was filtered ofi anddried in a vacuum desiccator.

The dried sodium salt was suspended in 25 cc. of ether and 25 cc. of 50%sulfuric acid was added in small portions until the mixture wasdefinitely acid. cc. of ether was added to bring about complete solutionof all solids. The aqueous layer was separated and extracted once with50 cc. of ether.

The combined ethereal solutions were dried over anhydrous magnesiumsulfate and then evaporated on the steam bath to a small volume,whereupon 3-acetoxy-7,1ldiketo-bis norallocholanic acid (II)crystallized out. The product was recrystallized from ether; M.P.235-238 C., [m] =24.6, 04:0.68, C=1.38% CHCl Analysis.--Calcd for C H OC, 68.87; H, 8.19. Found: C, 68.67; H, 8.04.

mg. of 3-acetoxy-7,11-diketo-bisnorallocholanic acid was suspended in 25cc. of ether and esterified with diazomethane. Al-l solid dissolved andon evaporation of the ether to a small volume, the methyl ester (III)crystallized. M.P. 226.5229 C. Mixed melting point with an authenticsample of the ester: 227-230 C.

5 g. of methyl 3-acetoxy-7,ll-diketo-bisnorallocholanate (III) and 2.07g. of powdered potassium hydroxide were placed in a 50 cc. round-bottomflask. 25 cc. of diethylene glycol and 2.3 cc. of 85 hydrazine hydratewere added and the temperature raised to -140 C. and held for 1 hour.The temperature was then raised to 195-200 C. and held for 2 hours.

After cooling, the reaction mixture was dissolved in benzene and water,50% sulfuric acid added until an acid reaction was obtained. The benzenelayer was separated, and the aqueous layer extracted three times with 50cc. of benzene. The combined benzene solutions were washed with waterand dried over anhydrous magnesium sulfate.

The benzene was treated with Darco. The benzene solution wasconcentrated in vacuo to dryness, the residue was dissolved in ether andesterifi'ed with an ethereal solution of diazomethane. The ether wasevaporated, and the methyl 3-hydroxy-l1-keto bisnorallocholanate (IV)was recrystallized from methanol, M.P. 177.5-180.5. Mixed M.P. with anauthentic sample, 177-179 C., [a] =+41.

EXAMPLE 5 Preparation of S-hydroxy-l1-kez0bisn0rall0ch0lanic acid andits methyl ester from 3-acet0xy-7,1I-diketobisnorallocholanic acid Twograms of 3acetoxy-7,l1-diketobisnorallocholanic acid (prepared asdescribed in Example 4) were stirred in a 50 cc. round bottom flask with15 cc. of diethylene glycol, 1.5 g. of powdered potassium hydroxide and1.5 cc. of 85% hydrazine hydrate and the temperature raised slowly to-140 C. and held for 45 minutes. The temperature was then raised to -l95C. and held for one hour.

After cooling the reaction mixture was acidified with 2 N sulfuric acid,diluted with 30 cc. of distilled water and filtered. The tan, dried cakeweighed 1.57 g. The product was dissolved in benzene-ethanol, treatedwith Darco, filtered through Supercel and the filtrate was concentrateduntil crystallization started. Recrystallization from benzene gave 0.60g. of product melting at 258 to 261.4 C.

Analysis.Calculated for C H O C, 72.89; H, 9.45. Found: C, 72.82; H,9.34.

An additional 0.60 g. of lower melting acid (M.P. 252- 258) wasrecovered from the mother liquors of the above product.

A sample of the acid was esterified with diazomethane Preparation ofll-ketotigogeniri from 3-acet0xy-7,l1-'diketotigogenin .A mixture .of'0:42 g. of 3-acetoXy-7,1l-diketotigogenin, 2.1' nil. of 'diethyleneglycol, 0.20 g. of powdered potassium hydroxide, and 0.21 ml. ofhydrazine hydrate (85%) was stirred; while being heated in an oil bath.The temperature was raisedlto 120-30 C. and held there for fifteenminutes. The temperature was then raised to 195-260 C. for 45 minutes.After cooling, the mixture was poured into 25 ml. of ice water mixtureand the resultingmixture was neutralized with dilute sulfuric acid. Thesolid product'was'reinov'ed by filtration and was washed well withwater. The dried crude product was dissolved"in.'20 ml. of methanol, andboiled for five minutes with a small amount of activated charcoal. Afterremoving the charcoal by filtration, the methanol solution wasconcentrated to ten ml. Water was added to the hot solution untilcrystallization was incipient. Upon cool 25 2,798,082-

8 ing, 0.22 g. of ll-ketotigogenin in the form of needles e. Obtai ed,.M- 2. .0. R y t l zed from a mixture of. ethyl acetate-petroleum.ether, the product melted at 222-226 C.

Found: 2, 75. 10; 10;20;

ll-ketoti 'gogenin'acetate was made by rel-inking 1 i-ketotigogenin fwith acetic. anhydride' Recrystallized" from methanoL it me'ltedat224.229 C. n V I Various changes and' modifications mayibe rnad e incarryingout the present invention without'departing from the spirit andscope thereof; Insofar as these changes and modifications are within thepurview ofthe annexed claimsQthy are to be considered as part of ourinvention.

W Q i LH I 1. A compoundfrorn the groupcon's'isti'ngof 3-.hydr'oxy-Whereirr'the acyl substituentis a lower fatty acid radical.

2. 3-hydroxy-1.l keto-A ergostene," 3. 3-a'cetoxy-1l-keto A -ergostene.

Refer nces Citedj'intlie file of this patent UNITED STATES PATENTSChemerda July 2, 1957'

1. A COMPOUND FROM THE GROUP CONSISTING OF3-HYDROXY11-KETO-$22-ERGOSTENE ANS 3-ACYLOXY-11-KETO$22-ERGOSTENEWHEREIN THE ACYL SUBSTITUENT IS A LOWER FATTY ACID RADICAL.